Extreme ultraviolet lithography is one of the most promising techniques for manufacturing integrated circuits (ICs) with ever smaller feature sizes. One method for generating extreme ultraviolet radiation is laser produced plasma, where tiny droplets of metals such as tin are heated to very high temperatures in a chamber using a high intensity laser beam such as that of a carbon dioxide laser. The heat ionizes tin atoms to form a tin plasma which radiates extreme ultraviolet when coming back to ground state. The process generates metal particles which can contaminate optics within the chamber as well as potentially outside the chamber where the extreme ultraviolet radiation is directed. One method for reducing the contamination from metal vapor is by introducing a gas such as hydrogen into the chamber to reduce the metal particles and convert them into gaseous matter that can be removed through the chamber exhaust.